// usefull junk 
/*
class Test {

  collision_detector a;
  particle one;
  particle two;
  gravity g;

  particle_group group;
  system system;

  Test() {

    a = new collision_detector();
    one = new particle();
    two = new particle();
    g = new gravity();

    group = new particle_group(5);
    system = new system(group);
  }

  void gravity() {

    one.mass = 1;
    two.mass = 1;

    g.set_particle_one(one);

    g.set_distance(distance(one.x_loc,one.y_loc,two.x_loc,two.y_loc));
    g.apply_gravity(two);


    println("///////////////");
    println(g.strength);
    println(one.rotation);
    println(two.rotation);

    one.math();
    two.math();

    one.render();
    two.render();
  }

  void collision() {


    one.x_loc = 10;
    one.y_loc = 10;
    two.x_loc = 10;
    two.y_loc = 10;

    a.set_particle_one(one);
    a.is_collision(two);

    println(a.distance);
    println(a.one.radius);
    println(a.collision);
  }

}

*/

